Fractions (Adv)

Taken from another post. How would you evaluate that fraction, or specifically (out of my homework) 4rt(81) [note that the 4 is the n). I got the bright idea that it might be rooted 4 times, but I get rt(3) and my math book says it's simply 3. Please explain.

Taken from another post. How would you evaluate that fraction, or specifically (out of my homework) 4rt(81) [note that the 4 is the n). I got the bright idea that it might be rooted 4 times, but I get rt(3) and my math book says it's simply 3. Please explain.

Thanks in advance.

Observe that

So to find , square root 81 twice, once to get 9 and a second time to get the answer: 3.

Raising a number to the one-fourth power does not mean that you are square rooting it four times. Instead, it is asking: which number multiplied by itself four times gets you the original number? In other words, which number multiplied by itself four times gets you 81? That number is defined as , or 3.

So to find , square root 81 twice, once to get 9 and a second time to get the answer: 3.

Raising a number to the one-fourth power does not mean that you are square rooting it four times. Instead, it is asking: which number multiplied by itself four times gets you the original number? In other words, which number multiplied by itself four times gets you 81? That number is defined as , or 3.